The gunman, who live-streamed the attacks on Friday from a head-mounted camera, identified himself as Brenton Tarrant in the footage, which showed him shooting at men, women and children.

All of the social media firms sent messages of sympathy to the victims of the mass shootings, reiterating that they act quickly to remove inappropriate content.

Facebook said: “New Zealand Police alerted us to a video on Facebook shortly after the live-stream commenced and we removed both the shooter’s Facebook account and the video.”

Mr Javid responded to a YouTube tweet which said it was “working vigilantly” to remove any violent footage by saying that the digital companies needed to “take some ownership”.

The attacks in Christchurch happened as people were attending the mosques for prayers.

Mr Javid said he had been left “sick to the stomach by the massacre of 49 innocent worshippers”.

He wrote: “They were simply targeted for being Muslims, as they paid respects to God.

“My own late father never missed Friday prayers. I often joined him, and I fondly look back on the peaceful moments we shared.”

Vigils for the victims took place in the UK on Friday, amid an outpouring of support for Britain’s Muslim community.

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Britain’s most senior Jewish faith leader Chief Rabbi Mirvis offered his condolences, and said the attacks were “terrorism of the most despicable kind, callously planned and motivated by the scourge of Islamophobia”.